Contribution of C-reactive protein to predicting overall survival in patients with advanced urothelial carcinoma: Development of a nomogram and evaluation by decision curve analysis.

Abstract

280 Background: To accurately estimate the individual survival of patients with advanced urothelial carcinoma (UC), the application of prediction models such as nomograms has been warranted in clinical use. We therefore constructed a nomogram which included C-reactive protein (CRP) as a novel biomarker in order to increase its predictive accuracy. Furthermore, the clinical usefulness of this nomogram was evaluated by decision curve analysis which incorporated the negative consequences of each decision to generate a net benefit (Vickers et al, BMC Med Inform Decis Mak, 2008). Methods: A total of 232 consecutive patients with locally advanced or metastatic urothelial carcinoma (UC) were treated at our institute. Among them, 9 patients with missing data were excluded. The current study cohort was comprised of the remaining 223 patients. A nomogram predicting 6- and 12-month survival probability was developed based on the results of the final multivariate analytic model. To evaluate the efficacy of this nomogram, a quantified concordance-index (c-index) was computed and a decision curve analysis was performed. Results: Overall, 184 patients died of the primary disease and the remaining 39 were censored. The median follow-up period and length of overall survival were 5 and 6 months, respectively. The 6- and 12-month survival rates were 48% and 30% respectively. A nomogram was developed which included the parameters of age, PS, visceral metastasis, hemoglobin and CRP. The c-index of this prediction model was 0.79 compared with 0.75 for that of a model without CRP. The decision curve analysis revealed that a novel nomogram which incorporated CRP had a superior net benefit to that without CRP for most of the examined threshold probabilities. Conclusions: Incorporation of CRP increased the predictive accuracy of a prognostic nomogram for advanced UC. In clinical practice, this nomogram would contribute to the decision making process in the treatment of patients suffering from this form of carcinoma.